11. A boy wants to throw a ball from a point A so as to just clear the obstruction at B. The minimum horizontal velocity with which the boy should throw the ball is (A) `23.5 ms^(-1)` (B) `47 ms^(-1)` (C) `235 ms^(-1)` (D) `32.5 ms^(-1)`

An aeroplane is moving horizontally at 30ms^(-1) at a height of 1km towards a target on the ground which is intended to be bombed The velocity with which bomb hits the target is (A) 100ms^(-1) (B) 200ms^(-1) (C) 144.6ms^(-1) (D) 150ms^(-1)

A body is projected horizontally from the top of the tower.It strikes the ground at an angle of 45^(0) after 5 Sec. The velocity of projection is (A) 19.6ms^(-1) (B) 39.2ms^(-1) (C) 49.0ms^(-1) (D) 29.4ms^(-1)

A man is standing on a rail road car travelling with a constant speed of v = 10 ms^-1 (Fig . 5.34). He wishes to throw a ball through a stationary hoop 5 m above the height of his hands in such a manner that the ball will move horizontally as it passes through the hoop. He throws the ball with a speed of 12.5 ms^-1 w.r.t. himself. (a) What must be the vertical component of the initial velocity of the ball ? (b) How many seconds after he releases the ball will it pass through the hoop ? ( c) At what horizontal distance in front of the loop must he release the ball ? .

A man is standing on a rail road car travelling with a constant speed of v = 10 ms^-1 (Fig . 5.34). He wishes to throw a ball through a stationary hoop 5 m above the height of his hands in such a manner that the ball will move horizontally as it passes through the hoop. He throws the ball with a speed of 12.5 ms^-1 w.r.t. himself. (a) What must be the vertical component of the initial velocity of the ball ? (b) How many seconds after he releases the ball will it pass through the hoop ? ( c) At what horizontal distance in front of the loop must he release the ball ? .

A ball is thrown horizontally from the top of a tower with a velocity of 40ms-1 .' Take g = 10 ms^2 '

The height and horizontal distances covered by a projectile in a time t are given by y=(4t-5t^(2)) m and x=3t m the velocity of projection is (A) 4ms^(-1) (B) 3ms^(-1) (C) 5ms^(-1) (D) 10ms^(-1)

A boy throws a ball of mass 200g with a velocity 20ms^-1 at an angle of 40° with the horizontal. What is the kinetic energy of the ball at the highest point of the trajectory?

A ball of mass 0.5 kg slows down from a speed of 5ms^-1 to 3ms^-1 , calculate the change in the kinetic energy of the ball.